Alkenyl compounds

ABSTRACT

Cured resins of high fracture toughness are prepared from N,N&#39;-bisimides of formula I ##STR1## and alkenyl compounds of formula II 
     
         D(G).sub.m                                                 II 
    
     in which D is an m-valent group and G represents a phenyl ring having at least one alkenyl (e.g. allyl or 1-propenyl) substituent.

CROSS-REFERENCE

This is a division of Ser. No. 942,696 filed Dec. 17, 1986, now U.S.Pat. No. 4,789,704.

The present invention relates to curable resins which are used toprepare cured resins of high fracture toughness.

According to a first aspect of the present invention curable resinscomprise a mixture of

(a) at least one N,N'-bisimide of an unsaturated dicarboxylic acid offormula I ##STR2## in which B represents a divalent radical containing acarbon-carbon double bond and A is a divalent radical containing atleast two carbon atoms and

(b) at least one alkenyl compound of formula II

    D(G).sub.m                                                 II

in which m is an integer from 1 to 4, G represents a phenyl ringsubstituted by at least one alkenyl group and D represents (i) a groupof formula IIa

    E--[OCH.sub.2 CH(OH)CH.sub.2 O--].sub.n                    IIa

in which E is a n-valent group and n is an integer from 1 to 4, (ii) adivalent group of formula IIb ##STR3## in which F is a divalent groupchosen from --SO₂ --, --SO--, --CMe₂₋₋, --O--, --C(CF₃)₂ --, --CH₂ -- or--CO--, (iii) a group of formula IIc ##STR4## in which F is as definedin (ii) above, (iv) a divalent group of formula IId ##STR5## or (v) adivalent group of formula IIe ##STR6## in which J is a divalent groupchosen from --SO₂ --, --SO--, --CMe₂ --, --O--, --C(CF₃)₂ --, --CH₂ --or --CO-- and p is 0 or 1.

The radical designated A in general formula I may be (a) an alkylenegroup with up to 12 carbon atoms, (b) a cycloalkylene group with 5 to 6carbon atoms, (c) a heterocyclic group with 4 to 5 carbon atoms and atleast one nitrogen, oxygen or sulphur atom in the ring, (d) a mono ordicarbocyclic group, (e) at least two mono or dicarbocyclic aromatic orcycloalkylene groups which are connected to one another by a directcarbon-carbon bond or by a bivalent group chosen from oxygen, sulphur,alkylene with one to three carbon atoms, or a group of formula IIIa toIIIj ##STR7## the radicals R₁, R₂, R₃, R₄, being alkyl groups with oneto five carbon atoms, R₅ being an alkylene group or an arylene group.

The radical B in the general formula I represents a divalent organicradical containing a carbon-carbon double bond. The radical B may have astructure as shown in formula IV, V, VI or VII ##STR8## Bismaleimides offormula I in which the radical B is of formula IV may be used forproducing the new curable resins of the present invention. Examples ofsuitable bismaleimides are 1,2-bismaleimidoethane,1,6-bismaleimidohexane, 1,12-bismaleimidododecane,1,6-bismaleimido(2,2,4-trimethyl)hexane, 1,3-bismaleimidobenzene,1,4-bismaleimidobenzene, 4,4'-bismaleimidodiphenylmethane,4,4'-bismaleimidodiphenylether, 4,4'-bismaleimidodiphenylsulphide,3,3'-bismaleimidodiphenylsulphone, 4,4'-bismaleimidodiphenylsulphone4,4'-bismaleimidodicyclohexylmethane, 2,4-bismaleimidotoluene,2,6-bismaleimidotoluene, 2,4-bismaleimidoanisole,N,N'-m-xylylenebismaleimide, N,N'-p-xylylenebismaleimide. Examples ofother suitable bisimides are N,N'-m-phenylene-biscitraconomide andN,N'-4,4'-diphenylmethane-citraconimide, in which the radical B is offormula VI and N,N'-4,4'-diphenylmethane-bis-itaconomide in which theradical B is of formula VII. Mixtures of bisimides may be used.Preferred mixtures of bismaleimides are those which form low meltingeutectic mixtures for example i) eutectic mixtures containing4,4'-bismaleimidodiphenylmethane and 2,4-bismaleimidotoluene, ii)eutectic mixtures containing 4,4'-bismaleimidodiphenylmethane,2,4-bismaleimidotoluene and 1,6-bismaleimido(2,2,4-trimethyl)hexane andiii) eutectic mixtures of 4,4'-bismaleimidodiphenylmethane and2,4-bismaleimidoanisole.

The bisimides of formula I may be modified with amino acid hydrazides(for example m-aminobenzoic acid hydrazide), polyamines, polyhydrazides,azomethines, polyisocyanates, carboxy-terminated oracrylic/vinyl-terminated polybutadiene/acrylonitrile elastomers,thermoplastic polymers (for example polysulphones, polyhydantoins andpolyimides) or mixtures thereof. These modified bisimides are used in asimilar manner to that described herein for bisimides of formula I toprepare curable resins of the present invention.

In the alkenyl compounds of formula II, G may represent a phenyl ringcarrying one or more allyl or 1-propenyl substituents. Additionalsubstituents (for example methoxy) may also be present.

In alkenyl compounds of formula II in which D represents a polyvalentgroup of formula IIa, the group E may be (i) an alkylene group, (ii) acycloalkylene group containing 5 or 6 carbon atoms, (iii) phenylene,(iv) a heterocyclic group containing at least one nitrogen, oxygen orsulphur atom in the ring, (v) a mono or dicarbocyclic group, (vi) agroup of formula IIf

    K--(L).sub.q --K                                           IIf

in which K represents an optionally substituted mono or dicarbocyclicaromatic or cycloalkylene group, q is 0 or 1 and L is a divalent groupselected from --SO₂ --, --SO--, --CMe₂ --, --O--, --C(CF₃)₂ --, --CH₂ --or --CO-- or (viii) a high molecular weight epoxy resin (for example anepoxy resin formed by the reaction of epoxy compounds with bisphenol A).Alkenyl compounds of formula II in which D represents a group of formulaIIa may be prepared by the reaction of epoxy compounds withalkenylphenols such as o-allylphenol, p-allylphenol, eugenol,isoeugenol, o-(1-propenyl)phenol or p-(1-propenyl)phenol (anol) attemperatures between 80° and 150° C. in the presence of a catalyst suchas triphenylphosphine or alkyltriphenylphosphonium halides. The reactionmay be performed in the presence of an inert organic solventor in theabsence of a diluent. The amount of alkenylphenol present may be suchthat no residual epoxy groups remain at the end of the reaction or theamount of alkenylphenol may be lower than a stoichiometric amount togive a compound containing unreacted epoxy groups. One group ofpreferred alkenyl compounds of formula II may be represented by formulaIIg

    G[OCH.sub.2 CH(OH)CH.sub.2 O]E[OCH.sub.2 CH(OH)CH.sub.2 O]G

in which E is a m-phenylene group or a group of formula IIh ##STR9## andG represents a group of formula IIj or IIk ##STR10## or of formula IImor IIn ##STR11## The preferred compounds of formula II in which Grepresents groups of formulae IIj and IIm may be prepared by thereaction of one mole of 4,4'-bisglycidylbisphenol A with 2 moles ofo-allylphenol or eugenol respectively.

Alkenyl compounds of formula II in which D represents a divalent groupof formula IIb, may be prepared by the reaction of an alkenylphenol witha compound of formula VIII ##STR12## in which X represents halo.Preferred alkenyl compounds in which F is --SO₂ -- may be prepared byheating alkenylphenols with a dichlorodiphenylsulphone at a temperatureof around 170°-190° C. in the presence of a solvent (for exampleN-methylpyrrolidone) and a catalyst (for example potassium carbonate).Preferred alkenyl compounds in which F is --CO-- may be prepared byheating alkenylphenols (for example allylphenol, eugenol ordiallybisphenol A) with a difluorobenzophenone at a temperature ofaround 140°-160° C. in the presence of a solvent (for exampleN-methylpyrrolidone) and a catalyst (for example potassium carbonate). Afurther group of preferred compounds of formula II may be represented byformula IIp ##STR13## in which F is --SO₂ -- or --CO-- and G is a groupof formula IIk or IIn. These preferred compounds are prepared by thereaction of allylphenol or eugenol with 4,4'-dichlorodiphenylsulphone or4,4'-difluorobenzophenone or 2,4'-difluorobenzophenone under theconditions outlined above to give products in which the allyl groupshave isomerised to form 1-propenyl groups.

Alkenyl compounds of formula II in which D represents a group of formulaIIc may be prepared by the reaction of an alkenylphenol with a compoundof formula IX ##STR14## in which X represents halo. Preferred compoundsin which F is --CO-- may be prepared by heating an alkenylphenol with afluorobenzophenone in the presence of a catalyst (such as potassiumcarbonate). To prepare these preferred compounds in which G is a groupof formula IIk and IIn, allylphenol or eugenol are heated to atemperature of 150°-165° C. with 4-fluorobenzophenone to give a productin which the allyl group has isomerised to a 1-propenyl group.

Alkenyl compounds of formula II in which D represents a group of formulaIId or IIe may be prepared by the reaction of the acid chloride of adicarboxylic acid of formula X or of formula XI ##STR15## with analkenylphenol [for example o-allylphenol, p-allylphenol, eugenol,isoeugenol, o-(1-propenyl)phenol or p-(1-propenyl)phenol].

The ratio of the number of moles of bisimide present to the number ofmoles of alkenyl compound present in the curable resins of the presentinvention may lie in the range 1:1 to 50:1, preferably in the range 1:1to 20:1, most preferably in the range 2:1 to 10:1.

The preparation of the new curable resins may be carried out in an inertorganic solvent or diluent, for example in dimethylformamide,dimethylacetamide, N-methyl pyrrolidone and tetramethyl urea, or ketonetype solvents such as acetone, methylethyl ketone, methyl isobutylketone and cyclohexanone or chlorinated solvents such as methylenechloride, ethyl chloride, 1,2-dichloroethane and ether-type solventssuch as dioxane, tetrahydrofuran, ethyl glycol and ester type solventssuch as ethyl acetate or mixed glycol ether-esters such as ethyl glycolacetate, methyl glycol acetate, diethylene glycol diethyl ether,diethylene glycol monoethyl ether acetate etc. in such a manner thatprepolymer solutions are obtained. The prepolymer can be isolated bystripping off the solvent either in vacuum or by heat or both, thusproviding a solventless resin that can either be processed from the meltor as a powder. The production of the new curable resins according tothis invention can also be carried out in inert diluents in which eitheronly one of the starting materials is completely soluble or all thestarting components are completely soluble. The latter procedure ispreferred when the application of the resin requires a solution as isthe case for the production of prepregs.

The preparation of the new curable resins may alternatively be performedby using conventional techniques for mixing and grinding of powders orpowders and liquids to intimately blend the bismaleimides with the othercomponents. In this case prepolymers are obtained by heating thehomogeneous mixture at a temperature between 80°and 200° C., forsufficient time to produce a still formable and soluble product.

For many industrial applications of the new curable resins of thepresent invention, it is advantageous to accelerate the curing processby adding catalysts. The catalysts may be present in an amount of 0.01to 10% by weight (preferably 0.5 to 5% by weight) based on the totalweight of the curable bisimide resin. Suitable catalysts include ionicand free radical polymerisation catalysts. Examples of ionic catalystsare (a) alkali metal compounds for example alkali metal alcoholates suchas sodium methylate or alkali metal hydroxides, (b) monoamines such asbenzylamine, diethylamine, trimethylamine, triethylamine, tributylamine,triamylamine, N,N-dimethylaniline, N,N-dimethylbenzylamine,tetramethyldiaminodiphenylmethane, N,N-diisobutylaminoacetonitrile andN,N-dibutylaminoacetonitrile, (c) heterocyclic amines such as quinoline,N-methylpyrrolidine, imidazole, benzimidazole, N-methylmorpholine andazabicyclooctane, (d) polyamines containing several amino groups ofdifferent types such as mixed secondary/tertiary polyamines, (e)quaternary ammonium compounds such as benzyltrimethylammonium hydroxideand benzyltrimethylammonium methoxide and (f) mercaptobenzothiazole.Examples of free radical polymerisation catalysts include (a) organicperoxides such as ditertiary butyl peroxide, diamylperoxide andt-butylperbenzoate and (b) azo compounds such as azoisobutyronitrile.Further catalysts which can be used are metal acetylacetonatesespecially transition metal acetylacetonates such as vanadiumacetylacetonates.

The catalysts can be admixed with the components of the curable resinsor they may be added during the production of the prepolymers either bya powder blending process or by the solvent blending process describedabove.

In many cases the new curable resins of the present invention may beprocessed from the melt. To reduce the melt viscosity and to improve thepot life the resins can be blended with so-called reactive diluents,preferably those that are liquid at room temperature. The reactivediluents that may be employed carry one or more polymerizable doublebonds of the general formula XII ##STR16## and may be of the vinyl-,allyl- or acryloyl-type. These reactive diluents can be of the ether,ester, hydrocarbon or heterocyclic type. Typical ethers that may beemployed are vinylallylether, diallylether, methallylether andvinylphenylether. Typical esters are vinyl-, allyl-, methylallyl-,1-chlorallyl-, crotyl-, isopropenyl esters derived from saturated orunsaturated aliphatic or aromatic mono- or polycarboxylic acids such asformic, acetic, propionic, butyric, oxalic, malonic, adipic, sebacic,acrylic, methacrylic, phenylacrylic, crotonic, maleic, fumaric,itaconic, citraconic, tetrahyrophthalic, benzoic, phenylacetic,o-phthalic, isophthalic or terephthalic acid and naphthalic-dicarboxylicacid or mixtures thereof. The most important hydrocarbon type reactivediluents to be used are styrene, methylstyrene, vinylhexane,vinylcyclohexane, divinylbenzene, divinyl cyclohexane, diallybenzene,vinyltoluene and 1-vinyl-4-ethyl-benzene or mixtures thereof. Examplesof heterocyclic type reactive diluents are vinylpyridine andvinylpyrrolidine.

In those cases where reactive diluents are used it is possible to firstblend the bisimide components with the reactive diluent and then theother components of the curable resins are added. The quantity ofreactive diluent that may be employed can be up to 80% by weight of thetotal final resin mixture.

Very advantageous reactive diluents are styrene and divinylbenzene whichare used in quantities up to 30% of the total resin mixture. Care has tobe taken with these diluents because they crosslink at very lowtemperatures, at around 100°-110° C., therefore mixtures containingthese diluents have to be prepared at temperatures well below 100° C.

The new curable resins of the present invention can be further modifiedwith unsaturated polyester resins. Useful unsaturated polyesters arewell known products which are prepared by polycondensation ofpolycarboxylic acid derivatives such as esters with polyglycols asdescribed in detail in Kunststoffhandbuch, Band VII, p. 247-282, CarlHanser Verlag, Munchen 1973. Solutions of these polyesters in thereactive diluents described above can be used instead of the reactivediluent alone to modify the new resins.

The new curable resins of the present invention either modified or notor prepolymers prepared therefrom can be thermally converted tocrosslinked polymers by heating them to temperatures of between 80° and400° C., for a time sufficient to complete cure.

The new curable resins are advantageously used to produce laminatedmaterials. In such a case the curable resins or prepolvmers producedfrom the curable resins are dissolved in suitable solvents to provide a25-65% by weight solution, which is used to impregnate (a) glass fibresin the form of fabrics or rovings or (b) carbon fibres, boron fibres ororganic synthetic fibres in the form of fabrics, filaments or rovings.The fibres are impregnated with this solution and then the solvent isremoved by drying. The fibres which are impregnated with the curableresins of the present invention are then moulded into laminate form bythe application of pressure and temperature, as is well known in the artto provide a laminated material in which the crosslinked polymer is thebinder. Suitable solvents include dimethylformamide, dimethylacetamide,N-methyl pyrrolidone, tetramethyl urea, acetone, methyl-ethyl ketone,methyl-isobutyl ketone, cyclohexanone, methylene chloride, ethylchloride, 1,2-dichloroethane, dioxane, tetrahydrofuran, ethyl glycol,ethyl acetate, ethyl glycol acetate, methyl glycol acetate,diethyleneglycol diethyl ether, diethyleneglycol monoethyl ether acetateand mixtures thereof.

The curable resins according to the invention can also be processed bythe known methods of the powder moulding industry in relation to curablecompositions, to produce mouldings, curing taking place withsimultaneous shaping under pressure. For these applications the curableresins are admixed with additives such as fillers, colourants, softenersand flameproofing agents. Ideal fillers are for example glass fibres,carbon fibres, organic high modulus fibres such as aramids, quartzflour, kaolin, silica, ceramics and metals in the form of fine powdersfor example produced by micronisation.

One of the preferred uses of the new resin composition is as binders forfibre composites. For this application fibres such as glass, graphite oraramids in the form of rovings, fabrics or short fibremats, or felts areimpregnated with the composition, employing resin solution as mentionedabove to impregnate said reinforcements. After stripping off or dryingoff the solvent employed a prepreg is left, which in the second phasemay be cured at a temperature between 180° and 350° C., optionally underpressure.

In another preferred use of the resin compositions of the presentinvention the resin is cast into film and sheets of film are stackedalternately with layers of reinforcing material for example glass fibre.The resulting stack is subjected to heat and pressure to form alaminated structure.

The curable resins produced by the present invention are used to producecured resins which have high fracture toughness. This invention isillustrated by the following Examples which are given by way of exampleonly. In the Examples the fracture toughness is measured by a methodderived from that described in ASTM E399-78 in which a bar of resin51.25 mm long, 6.25 mm wide and 12.5 mm deep is cut from a casting and agroove 5.4 to 6.0 mm deep is cut centrally across the width of the bar.The base of the groove is scored once along its length prior toperforming the test.

EXAMPLE 1 Synthesis of o-allylphenol/4,4'-bisglycidylbisphenol-A adduct

o-Allylphenol (576.9 g), 4,4'-bisglycidylbisphenol A-epoxy resin (740 g)(Rutapox 0164) and triphenylethylphosphonium iodide (8 g) are placedinto a 3 necked flask equipped with a stirrer and thermometer and heatedunder nitrogen to 100° C. for 13 hours. The reaction product is thenheated to 140°-150° C. and degassified in vacuum to strip off excesso-allylphenol. The yield of o-allylphenol-4,4'-bisglycidylbisphenol-Aadduct is 1207.3 grammes. The adduct shows a viscosity of 1200±400 mPa.sat 70° C.

EXAMPLE 2 Synthesis of eugenol/4,4'-bisglycidylbisphenol-A adduct

Eugenol (133 g), 4,4'-bisglycidylbisphenol A-epoxy resin (140 g)(Rutapox 0164) and triphenylethylphosphonium iodide (1.84 g) are placedinto a 3 necked flask equipped with a stirrer and thermometer and heatedunder nitrogen to 100° C. for 13 hours. The reaction product is thenheated to 140°-150° C. and degassified in vacuum to strip off excesseugenol. The yield of eugenol-4,4'-bisglycidylbisphenol-A adduct is 245grammes. The adduct shows a viscosity of 3600 mPa.s at 70° C.

EXAMPLE 3 Synthesis of a o-allylphenyl/eugenol-4,4'-bisglycidylbisphenolA adduct

In a similar manner to that described in Example 1, o-allylphenol (64g), eugenol (78.4 g), 4,4'-bis-glycidylbisphenol-A (182.1 g) andtriphenylethylphosphonium iodide (0.97 g) are reacted to give an adduct(yield 302 g) which shows a viscocity of 2500 mPa.s at 70° C.

EXAMPLE 4 Synthesis of o-allylphenol/1,3-bisglycidylresorcinol adduct

In a similar manner to that described in Example 1, o-allylphenol (134g), 1,3-bisglycidylresorcinol (115.1 g), triphenylethylphosphoniumiodide (0.75 g) and methylglycolate (145 g) were reacted at 100° C. for13 hours. The solvent and excess o-allylphenol were removed by heatingat 140° C. finally in vacuo. The yield of adduct was 227.9 g and itshowed a viscocity of 280 mPa.s at 70° C.

EXAMPLE 5 Synthesis of 4,4'-bis[o-(1-propenyl)phenoxy]diphenylsulphone

o-Allylphenol (67 g), 4,4'-dichlorodiphenylsulphone (71.75 g), potassiumcarbonate (36.25 g), dry N-methylpyrrolidone (150 ml) and toluene (70ml) are placed in a 3-necked 1500 ml flask fitted with a stirrer, reflexcondensor and thermometer and the mixture is heated under nitrogen to atemperature between 170°-185° C. and stirred for 3 hours. Water andtoluene are separated via a Dean Stark trap and finally after 3.5 hoursthe reaction mixture reaches a temperature of 185° C. The mixture iscooled to 100° C. and a 1:1 mixture of toluene/water (600 ml) is addedwhile stirring. After phase separation the organic layer is washed twicewith toluene (150 ml) and the combined toluene layers are washed 3 timeswith water (300 ml). The toluene phase is dried over sodium sulphate andtoluene distilled off by use of a rotary evaporator finally in vacuumleaving 4,4'-bis[o-(1-propenyl)phenoxy]diphenylsulphone as a light brownmelt. The yield is 114 g.

EXAMPLE 6 Synthesis of4,4'bis-[o-methoxy-p-(1-propenyl)phenoxy]diphenylsulphone

In a similar manner to that described in Example 5 eugenol is employedfor the synthesis of4,4'-bis-[o-methoxy-p-(1-propenyl)phenoxy]diphenylsulphone.

EXAMPLE 7 Synthesis of o-allylphenol/bisphenolA/4,4'bisglycidylbisphenol A adduct

4,4'-bisglycidylbisphenol-A (152 g), bisphenol-A (45.6 g), o-allylphenol(53.6 g) and triphenylethylphosphoniumiodide (0.75 g) are reacted in astirred 3-necked flask at a temperature of 115° C. for 11 hours. Theadduct is finally degassified at 140° C. in vacuum. The yield of adductis 203.7 g and it shows a viscosity which is greater than 20000 mPa.s at70° C.

EXAMPLE 8 Synthesis of 4,4'-bis[o-(1-propenyl)phenoxy]benzophenone

o-Allylphenol (245.6 g), 4,4'-difluorobenzophenone (200 g), potassiumcarbonate (187.4 g), dry N-methylpyrrolidone (700 ml) and toluene (250ml) are placed in a 3-necked 2500 ml flask fitted with a stirrer, reflexcondensor and thermometer and the mixture is heated under nitrogen to atemperature between 145°-155° C. and stirred for 31/2 hours. Water andtoluene are separated via a Dean Stark trap and finally after 3.5 hoursthe reaction mixture reaches a temperature of 155° C. The mixture iscooled to 100° C. and a 1:1 mixture of toluene/water (1100 ml) is addedwhile stirring. After phase separation the aqueous layer is washed withtoluene (300 ml) and the combined toluene layers are washed 4 times withwater (400 ml). The toluene phase is dried over sodium sulphate andtoluene distilled off by use of a rotary evaporator finally in vacuumleaving 4,4'-bis[o-(1-propenyl)phenoxy]benzophenone as a light yellowmelt. The yield is 363.3 g.

The product has a melt viscosity of 280 mPa.s at 80° C.

EXAMPLE 9 Synthesis of4,4'-bis[o-methoxy-p-(1-propenyl)phenoxy]benzophenone

In a similar manner to that described in Example 8 eugenol is employedfor the synthesis of4,4'-bis[o-methoxy-p-(1-propenyl)phenoxy]benzophenone.

EXAMPLE 10 Synthesis of 2,4'-bis[o-(1-propenyl)phenoxy]benzophenone

o-Allylphenol (245.6 g), 2,4'-difluorobenzophenone (200 g), potassiumcarbonate (187.4 g), dry N-methylpyrrolidone (700 ml) and toluene (250ml) are placed in a 3-necked 2500 ml flask fitted with a stirrer, reflexcondensor and thermometer and the mixture is heated under nitrogen to atemperature of 160° C. and stirred for 8 hours. Water and toluene areseparated via a Dean Stark trap and finally after 8 hours the reactionmixture reaches a temperature of 160° C. The mixture is cooled to 100°C. and a 1:1 mixture of toluene/water (1100 ml) is added while stirring.After phase separation the aqueous layer is washed with toluene (200 ml)and the combined toluene layers are washed 4 times with water (400 ml).The toluene phase is dried over sodium sulphate and toluene distilledoff by use of a rotary evaporator finally in vacuum leaving2,4'-bis[o-(1-propenyl)phenoxy]benzophenone as a light yellow melt. Theyield is 396 g. The product has a melt viscosity of 350 mPa.s at 70° C.

EXAMPLE 11 Synthesis of2,4'-bis[o-methoxy-p-(1-propenyl)phenoxy]benzophenone

In a similar manner to that described in Example 10 eugenol is employedfor the synthesis of2,4'-bis[o-methoxy-p-(1-propenyl)phenoxy]benzophenone.

EXAMPLE 12 Synthesis of 4-[o-(1-propenyl)phenoxy]benzophenone

o-Allylphenol (33.5 g), 4-fluorobenzophenone (50.05 g), potassiumcarbonate (24.20 g), dry N-methylpyrrolidone (160 ml) and toluene (60ml) are placed in a 3-necked 500 ml flask fitted with a stirrer, reflexcondensor and thermometer and the mixture is heated under nitrogen to atemperature between 155°-160° C. and stirred for 3 hours. Water andtoluene are separated via a Dean Stark trap and finally after 3 hoursthe reaction mixture reaches a temperature of 160° C. The mixture iscooled to 100° C. and a 1:1 mixture of toluene/water (400 ml) is addedwhile stirring. After phase separation the aqueous layer is washed withtoluene (50 ml) and the combined toluene layers are washed 4 times withwater (150 ml). The toluene phase is dried over sodium sulphate andtoluene distilled off by use of a rotary evaporator finally in vacuumleaving 4-[o-(1-propenyl)phenoxy]benzophenone as a light yellow melt.The yield is 73 g.

EXAMPLE 13 Synthesis of a mixture of4,4'-bis[o-(1-propenyl)phenoxy]benzophenone and4-[o-(1-propenyl)phenoxy]benzophenone

o-Allylphenol (52.2 g), 4,4'-difluorobenzophenone (35 g),4-fluorobenzophenone (13.8 g), potassium carbonate (37.75 g), dryN-methylpyrrolidone (200 ml) and toluene (75 ml) are placed in a3-necked 1500 ml flask fitted with a stirrer, reflex condensor andthermometer and the mixture is heated under nitrogen to a temperaturebetween 155°-160° C. and stirred for 3 hours. Water and toluene areseparated via a Dean Stark trap and finally after 3 hours the reactionmixture reaches a temperature of 160° C. The mixture is cooled to 100°C. and a 1:1 mixture of toluene/water (400 ml) is added while stirring.After phase separation the aqueous layer is washed with toluene (100 ml)and the combined toluene layers are washed 4 times with water (150 ml).The toluene phase is dried over sodium sulphate and toluene distilledoff by use of a rotary evaporator finally in vacuum leaving a4,4'-bis-[o-(1-propenyl)phenoxy]benzophenone/4-[o-(1-propenyl)phenoxy]benzophenonemixture as a light yellow melt. The yield is 89 g.

EXAMPLE 14

80 grammes of a bismaleimide resin mixture containing 56 parts of4,4'-bismaleimidodiphenylmethane, 24 parts of 2,4-bismaleimidotolueneand 20 parts of 1,6-bismaleimido(2,2,4-trimethyl)hexane are melt blendedwith 25 g of the product of Example 1 at a temperature of 120° C. Thehomogeneous clear resin melt is degassed in vacuum and cast into aparallel epipedic steel mould and cured under pressure (5 bars) for 1hour at 190° C., plus 3 hours at 200° C. After demoulding the resincasting was post-cured for 5 hours at 210° C. plus 5 hours at 250° C.

Properties:

Density: 1.27 g/cm³

Flexural strength at 25° C.: 131 N/mm²

Flexural strength at 250° C.: 55 N/mm²

Flexural modulus at 25° C.: 3957 N/mm²

Flexural modulus at 250° C.: 1564 N/mm²

Fracture toughness at 25° C.: 400 J/m²

EXAMPLE 15

80 grammes of a bismaleimide resin mixture containing 56 parts of4,4'-bismaleimidodiphenylmethane, 24 parts of 2,4-bismaleimidotolueneand 20 parts of 1,6-bismaleimido(2,2,4-trimethyl)hexane are melt blendedwith 25 g of the product of Example 2 at a temperature of 120° C. Thehomogeneous clear resin melt is degassed in vacuum and cast into aparallel epipedic steel mould and cured under pressure (5 bars) for 1hour at 190° C., plus 2 hours at 200° C. After demoulding the resincasting was post-cured for 5 hours at 210° C. plus 5 hours at 250° C.

Properties:

Density: 1.29 g/cm³

Flexural strength at 25° C.: 127 N/mm²

Flexural strength at 250° C.: 66 N/mm²

Flexural modulus at 25° C.: 3673 N/mm²

Flexural modulus at 250° C.: 2290 N/mm²

Fracture toughness at 25° C.: 306 J/m²

EXAMPLE 16

65 grammes of 4,4'-bismaleimidodiphenylmethane and 35 grammes of theo-allylphenol/1,3-bisglycidylresorcinol adduct prepared as described inExample 4 and 0.017% of imidazole catalyst were melt blended at 160° C.The homogenous clear resin melt is cast into a parallel epipedic steelmould and cured under pressure (5 bars) for 1.5 hours at 180° C. plus 3hours at 200° C.

Properties:

Density: 1.28 g/cm³

Flexural strength at 25° C.: 145 N/mm²

Flexural strength at 250° C.: 65 N/mm²

Flexural modulus at 25° C.: 3556 N/mm²

Flexural modulus at 250° C.: 1842 N/mm²

Fracture toughness at 25° C.: 335 J/m²

EXAMPLE 17

80 grammes of a bismaleimide resin mixture containing 56 parts of4,4'-bismaleimidodiphenylmethane, 24 parts of 2,4-bismaleimidotolueneand 20 parts of 1,6-bismaleimido(2,2,4-trimethyl)hexane are melt blendedwith 25 g of the product of Example 5 at a temperature of 120° C. Thehomogeneous clear resin melt is degassed in vacuum and cast into aparallel epipedic steel mould and cured under pressure (5 bars) for 1hour at 190° C., plus 3 hours at 200° C. After demoulding the resincasting was post-cured for 5 hours at 210° C. plus 5 hours at 250° C.

Properties:

Density: 1.30 g/cm³

Flexural strength at 25° C.: 110 N/mm²

Flexural strength at 250° C.: 64 N/mm²

Flexural modulus at 25° C.: 3662 N/mm²

Flexural modulus at 250° C.: 2515 N/mm²

Fracture toughness at 25° C.: 389 J/m²

EXAMPLE 18

80 grammes of a bismaleimide resin mixture containing 56 parts of4,4'-bismaleimidodiphenylmethane, 24 parts of 2,4-bismaleimidotolueneand 20 parts of 1,6-bismaleimido(2,2,4-trimethyl)hexane are melt blendedwith 25 g of the product of Example 6 at a temperature of 120° C. Thehomogeneous clear resin melt is degassed in vacuum and cast into aparallel epipedic steel mould and cured under pressure (5 bars) for 1hour at 190° C., plus 3 hours at 200° C. After demoulding the resincasting was post-cured for 5 hours at 210° C. plus 5 hours at 250° C.

Properties:

Density: 1.28 g/cm³

Flexural strength at 25° C.: 112 N/mm²

Flexural strength at 250° C.: 78.5 N/mm²

Flexural modulus at 25° C.: 3684 N/mm²

Flexural modulus at 250° C.: 2659 N/mm²

Fracture toughness at 25° C.: 231 J/m²

EXAMPLE 19 to 22

a) Manufacture of Products

The procedure to blend and cure mixtures comprising bismaleimides ando-allylphenol-4,4'-diglycidylbisphenol-A adducts (prepared as describedin

Example 1) is as follows: A mixture of bismaleimides (150-250 g) as setout in Table 1 is blended with methylglycolacetate (200 g), followed byheating the mixture to temperatures of 120°-150° C. During heating thesolvent is stripped off and to the melt is added theo-allylphenol-4,4'-digly-cidylbisphenol-A adduct, prepared as describedin Example 1. The resulting mixture is melt blended at 120°-130° C. andfinally degassed in vacuum. Then the melt is cast into a parallelepipedic mould and cured for 1 hour at 180°-190° C., plus 3 hours at200°-210° C. under pressure of 4 bars. After demoulding, the resincasting is postcured for 2 hours at 210° C., plus 5 hours at 250° C.

(b) Mechanical Properties of Polymers

Flexural properties are determined according to DIN 53423 at 23°, 177°and 250° C. Fracture toughness is measured by the modified ASTM methoddescribed hereinbefore for products prepared according to themanufacturing procedure set out above and the results are given in Table1.

                                      TABLE 1                                     __________________________________________________________________________                 Product of                                                            BMI 1                                                                             BMI 2                                                                             Example 1                                                                           Test Temperature                                                                       FS   FM   G.sub.IC                                Example                                                                            (g) (g) (g)   (°C.)                                                                           (N/mm.sup.2)                                                                       (N/mm.sup.2)                                                                       J/m.sup.2                               __________________________________________________________________________    19   168 72   60    23      134.4                                                                              4230 151                                                        177      79   2895 --                                                         250      75   2259 --                                      20   147 63   90    23      152  3907 272                                                        177      98   2878 --                                                         250      80   2367 --                                      21   126 54  120    23      123  3870 446                                                        177      98   2328 --                                                         250      50   1239 --                                      22   105 45  150    23      132  4184 209                                                        177      17    380 --                                                         250      --   --   --                                      __________________________________________________________________________     BMI 1 = 4,4bismaleimidodiphenylmethane                                        BMI 2 = 2,4bismaleimidotoluene                                                FS = flexural strength                                                        FM = flexural modulus                                                         G.sub.IC =  fracture toughness                                           

EXAMPLES 23 to 27

(a) Manufacture of Products

The procedure to blend and cure mixtures comprising bismaleimides,aminobenzoic acid hydrazide and theo-allylphenol-4,4'-diglycidylbisphenol-A adduct prepared as described inExample 1 is as follows:

m-Aminobenzoic acid hydrazide is blended with methylglycolacetate (100g) and heated to 60° C. to obtain a solution. A mixture of bismaleimidesas set out in Table 2 is added to the solution together with additionalmethylglycolacetate (100 g) and the mixture is heated to 120° C. until ahomogeneous solution is obtained. Solvent is stripped off and to theremaining melt is added the o-allylphenol-4,4-diglycidyl-bisphenol-Aadduct of Example 1 and the resulting homogeneous melt is degassed invacuum. Then the melt is cast into a parallel epipedic mould and curedfor 1 hour at 180°-190° C., plus 3 hours at 200°-210° C., under pressureof 4 bars. After demoulding, the resin casting is post-cured for 2 hoursat 210° C., plus 5 hours at 250° C.

                                      TABLE 2                                     __________________________________________________________________________                      Product of                                                       BMI 1                                                                             BMI 2                                                                             m-ABH                                                                              Example 1                                                                           Test Temperature                                                                       FS   FM   G.sub.IC                           Example                                                                            (g) (g) (g)  (g)   (°C.)                                                                           (N/mm.sup.2)                                                                       (N/mm.sup.2)                                                                       J/m.sup.2                          __________________________________________________________________________    23   182.7                                                                             78.3                                                                              9    30     23      90   4227 145                                                        177      56   3174 --                                                         250      47   2487 --                                 24   172.2                                                                             73.8                                                                              9    45     23      114  4031 168                                                        177      67   3093 --                                                         250      60   2620 --                                 25   161.7                                                                             69.3                                                                              9    60     23      132  4086 178                                                        177      99   3124 --                                                         250      87   2715 --                                 26   149.1                                                                             63.9                                                                              9    78     23      127  3956 228                                                        177      81   2885 --                                                         250      74   2450 --                                 27   136.5                                                                             58.5                                                                              9    105    23      142  3736 344                                                        177      65   2127 --                                                         250      47   1428 --                                 __________________________________________________________________________     BMI 1 = 4,4bismaleimidodiphenylmethane                                        BMI 2 = 2,4bismaleimidotoluene                                                mABH = mAminobenzoic acid hydrazide                                           FS = flexural strength                                                        FM = flexural modulus                                                         G.sub.IC = fracture toughness                                            

EXAMPLES 28-43

(a) Manufacture of Products

m-Aminobenzoic acid hydrazide (4 parts) is blended with methylglycolateand heated to 60° C. to obtain a solution. A mixture of4,4'-bismaleimidodiphenylmethane (70 parts), 2,4-bismaleimidotoluene (30parts) and 1,6-bismaleimido(2,2,4-trimethyl)hexane (2 parts) andmethylglycolate was added and the mixture heated to 120° C. to give ahomogeneous solution. The solvent was stripped off to give a molten BMIblend. The weight of this blend given in Table 3 was taken and theweight of the product of Examples 5, 6, 8, 9, 10 or 11 was added to givea homogenous melt which was degassed in vacuum, cast into a parallelepipedic mould and cured for 4 hours at 140° C. and then for 12 hours at200°-210° C. under a pressure of 4 bars. After demoulding the casting ispost-cured for 5 hours at 250° C.

(b) Mechanical properties of cured polymers

Flexural properties are determined according to DIN 53423 at 25°, 17° 7and 250° C. Fracture toughness is measured by the modified ASTM methoddescribed hereinbefore. The properties of the cured polymers preparedaccording to the manufacturing procedure set out above and the resultsare given in Table 3 in which FS, FM and G_(Ic) have the meaning givenin Tables 1 and 2.

                                      TABLE 3                                     __________________________________________________________________________             Product                                                              BMI 1    of Ex.                                                                             Test Temperature                                                                       FS   FM   G.sub.IC                                     Example                                                                            (g) No.                                                                              (g)                                                                             (°C.)                                                                           (N/mm.sup.2)                                                                       (N/mm.sup.2)                                                                       J/m.sup.2                                    __________________________________________________________________________    28   80  5  20                                                                               23      113  3990 355                                                        250      73   2820 --                                           29   70  5  30                                                                               23      114  3940 230                                                        250      73   2620 --                                           30   60  5  40                                                                               23      114  3580 267                                                        250      73   2150 --                                           31   55  5  45                                                                               23      112  3740 227                                                        250      50   1670 --                                           32   50  5  50                                                                               23      112  3950 225                                                        250      26    910 --                                           33   80  6  20                                                                               23      87   3850 234                                                        177      62   3130 --                                                         250      56   2820 --                                           34   60  6  40                                                                               23      128  3490 378                                                        177      88   2690 --                                                         250      83   2380 --                                           35   80  8  20                                                                               23      106  3961 191                                                        177      75   3054 --                                                         250      65   2662 --                                           36   70  8  30                                                                               23      132  3607 397                                                        177      87   2744 --                                                         250      90   2470 --                                           37   60  8  40                                                                               23      132  3702 439                                                        177      84   2469 --                                                         250      55   1710 --                                           38   80  9  20                                                                               23      114  4171 247                                                        177      77   3132 --                                                         250      77   2472 --                                           39   70  9  30                                                                               23      119  3790 545                                                        177      86   3415 --                                                         250      85   2545 --                                           40   60  9  40                                                                               23      122  3594 466                                                        177      93   2790 --                                                         250      81   2435 --                                           41   80  10 20                                                                               23      104  3987 293                                                        177      64   3156 --                                                         250      66   2506 --                                           42   70  10 30                                                                               23      111  3871 323                                                        177      72   2923 --                                                         250      65   2501 --                                           43   60  10 40                                                                               23      82   3822 467                                                        177      64   2465 --                                                         250      50   1736 --                                           __________________________________________________________________________

EXAMPLE 44

80 grammes of a bismaleimide resin mixture containing 56 parts of4,4'-bismaleimidodiphenylmethane, 24 parts of 2,4-bismaleimidotolueneand 20 parts of 1,6-bismaleimido(2,2,4-trimethyl)hexane are melt blendedwith 50 g of the product of Example 7 at a temperature of 120° C. Thehomogeneous clear resin melt is degassed in vacuum and cast into aparallel epipedic steel mould and cured under pressure (5 bars) for 1hour at 190° C., plus 3 hours at 210° C. After demoulding the resincasting was post-cured for 5 hours at 210° C. plus 5 hours at 250° C.

Properties:

Density: 1.26 g/cm³

Flexural strength at 25° C.: 99 N/mm²

Flexural strength at 250° C.: 42 N/mm²

Flexural modulus at 25° C.: 3427 N/mm²

Flexural modulus at 250° C.: 1181 N/mm²

Fracture toughness at 25° C.: 207 J/m²

EXAMPLE 45

m-Aminobenzoic acid hydrazide (4 parts) is blended with methylglycolateand heated to 60° C. to obtain a solution. A mixture of4,4'-bismaleimidodiphenylmethane (70 parts), 2,4-bismaleimidotoluene (30parts) and 1,6-bismaleimido(2,2,4-trimethylhexane (2 parts) andmethylglycolate was added and the mixture heated to 120° C. to give ahomogeneous solution. The solvent was stripped off to give a molten BMIresin to which 66 parts of the product of Example 12 was added and meltblended. The homogeneous melt was degassed in vacuum, cast into aparallel epipedic mould and cured for 2 hours at 170° C., plus 4 hoursat 210° C., at a pressure of 4 bars. After demoulding, the casting ispost-cured for 5 hours at 240° C.

Properties:

Density: 1.26 g/cm³

Flexural strength at 25° C.: 116 N/mm²

Flexural strength at 177° C.: 60 N/mm²

Flexural modulus at 25° C.: 4013 N/mm²

Flexural modulus at 177° C.: 2080 N/mm²

Fracture toughness at 25° C.: 321 J/m²

We claim:
 1. An alkenyl compound of formula II

    D(G).sub.m                                                 II

in which m is an integer from 1 to 4, G represents a phenyl ringsubstituted by at least one alkenyl group and D represents (i) a groupof formula IIa

    E--[OCH.sub.2 CH(OH)CH.sub.2 O--].sub.n                    IIa

in which E is a n-valent group and n is an integer from 1 to 4, (ii) adivalent group of formula IIb ##STR17## in which F is a divalent groupchosen from --SO₂ --, --SO--, --CMe₂ --, --O--, --C(CF₃)₂ --, --CH₂ --or --CO-- , (iii) a group of formula IIc ##STR18## in which F is asdefined in (ii) above, (iv) a divalent group of formula IId ##STR19## or(v) a divalent group of formula IIe ##STR20## in which H is a divalentgroup chosen from --SO₂ --, --SO--, --CMe₂ --, --O--, --C(CF₃)₂ --, --CH₂ -- or --CO-- and p is 0 or
 1. 2. An alkenyl compound of formula IIg

    G[OCH.sub.2 CH(OH)CH.sub.2 O]G                             IIg

in which E is m-phenylene or a group of formula IIh ##STR21## and G is agroup of formula IIj, IIk, IIm or IIn ##STR22##
 3. Compound of formulaIIp ##STR23## in which F is --SO₂ -- or --CO-- and G represents a groupof formula IIk or IIn ##STR24##
 4. An alkenyl compound of the formula IIas claimed in claim 24, in which D is a divalent group of formula IIb,said alkenyl compound having been prepared by reaction of analkenylphenol with a compound of formula VIII ##STR25## in which F is--SO₂ --, --SO--, --CMe₂ --, --O--, --C(CF₃)₂ --, --CH₂ -- or --CH-- andX is halo.